1. Field of the Invention
The present invention relates in general to automated video production and more particularly to an automated system and method for producing videos using expert video production rules.
2. Related Art
A lecture (such as, for example, a meeting, a talk, a seminar, a presentation and classroom instruction) is an important tool whereby knowledge transfer, teaching and learning can occur. A lecture, which can be any setting whereby an exchange of information occurs, may include at least one lecturer and an audience. Universities and many corporations, inspired by both the increased emphasis on life-long learning and the rapid pace of technological change, are offering an ever-increasing selection of lectures to teach, train and inform students and employees. In order to accommodate all persons interested in a lecture and to manage the inevitable time conflicts that occur, many of these lectures are made accessible “online” over a computer network. Viewing a lecture online allows a person to remotely view the lecture either while the actual lecture is occurring (“live”) or at a later time (“on-demand”).
In order to facilitate viewing of a lecture both live and on-demand, the lecture must be made available (or published) online. Online publishing of a lecture enables a person to view the lecture at a time and location that is convenient for the person. Online publishing of lectures is becoming more feasible and popular due to continuous improvements in computer network infrastructure and streaming-media technologies. The popularity of publishing lecture online is gaining momentum slowly, however, and the fact remains that the majority of lectures that take place are not recorded or made available online. Two key barriers to online publishing are the cost of equipping lecture rooms with the equipment (such as cameras) needed to capture the lecture and the labor costs associated with having people produce the lecture video. Equipment cost is a one-time cost and tends to become less expensive as market demand increases. Labor cost for video production, however, is a recurring cost and one is of the main prohibitions to the online publishing of lectures.
As computer technology continues to advance, one alternative to hiring a human video production team is to construct a fully automated video production system that replaces human operators with machines. Automated video production systems and methods that are able to provide high-quality recordings are highly desirable because labor costs associated with video production are greatly reduced. Because labor costs are a major obstacle to recording lectures, reducing these labor costs by using high-quality automated video production techniques instead of a human video production team reduces at least some obstacles to online publishing of lectures.
There are a few existing automated video production systems and research prototypes. However, each of these systems has one of more of the following limitations:                Single camera setup: One disadvantage with a single camera setup is that there are long switching times between camera views. In other words, when switching between camera views, the single camera must be repositioned and this repositioning takes time. This causes a delay in the transition from a current camera view to a new camera view. Another disadvantage is that there is no backup camera in case the tracking device of the single camera fails, which can happen in a fully automated system.        Using invasive sensors to track lecturers: These sensors must be worn by the lecturer and may be bothersome to the lecturer and interfere with the lecturer's freedom of movement.        Simplistic directing rules: One disadvantage of having simplistic directing rules is that they do not automatically produce lecture videos that are of the same high quality as lecture videos produced by a professional human video production team. For example, many existing systems use directing rules that state camera views should be switched when a triggering event of a transition from one slide to another occurs.        Lack of an audience-tracking camera: Human video production teams know and studies have shown that the audience is an important and useful part of the lecture experience and include camera views of the audience when capturing the lecture. An audience camera can focus on an audience member who asks questions and can provide random audience shots to make the lecture more enjoyable for a viewer to watch. Leaving out camera views of the audience and those audience members who may ask questions by not providing an audience-tracking camera severely degrades the quality of the final lecture video.        
Accordingly, there exists a need for an automated video production technique that is automated to alleviate human labor costs associated with producing a lecture video. What is needed is an automated video production technique that captures lectures in a professional and high-quality manner using the similar rules used by professional human directors and cinematographers. What is further needed is an automated video production system that includes multiple cameras to enable fast switching of camera views, to allow a variety of camera views and to provide backup cameras in the case of camera failure. Moreover, what is needed is an automated video production technique that uses an audience-tracking camera to provide audience camera views and to make the lecture video more enjoyable for a viewer to watch. Moreover, what is needed is an automated video production system and method that tracks a lecturer in a lecture without the need for the lecturer to wear bothersome and restricting sensors, such that the lecturer remains unaware of the tracking. This type of automated video production technique takes into account the desires of the viewing audience and caters to these desires to make the production and viewing of lectures online an enjoyable experience while at the same time enhancing the learning process.